Add missing forward declarations

git-svn-id: http://root.cern.ch/svn/root/trunk@17620 27541ba8-7e3a-0410-8455-c3a389f83636

graf/inc/TGraph.h

-// @(#)root/graf:$Name:  $:$Id: TGraph.h,v 1.57 2006/11/24 10:17:46 brun Exp $
+// @(#)root/graf:$Name:  $:$Id: TGraph.h,v 1.58 2007/01/23 11:12:02 brun Exp $
 // Author: Rene Brun, Olivier Couet   12/12/94
 
 /*************************************************************************
@@ -44,6 +44,7 @@ class TBrowser;
 class TAxis;
 class TH1;
 class TH1F;
+class TCollection;
 class TF1;
 class TSpline;
 

tree/inc/TEntryList.h

-// @(#)root/tree:$Name:  $:$Id: TEntryList.h,v 1.4 2006/11/30 07:49:39 brun Exp $
+// @(#)root/tree:$Name:  $:$Id: TEntryList.h,v 1.5 2007/01/22 07:57:13 brun Exp $
 // Author: Anna Kreshuk 27/10/2006
 
 /*************************************************************************
@@ -21,6 +21,9 @@ class TDirectory;
 class TObjArray;
 class TString;
 
+class TList;
+class TCollection;
+
 class TEntryList: public TNamed 
 {
  protected: